The present invention relates to protective equipment, and, more particularly to liners for protective headgear and other protective equipment.
There have been many kinds of inflated liners for head protection helmets with pre-formed chambers or compartments interconnected by small air passages. In some instances foam plastic pads of combinations of densities have been enclosed within the compartments to assist in attenuating the force of an impact to the helmet when worn.
In other designs, means to regulate the flow of air between the chambers have been employed, such as, the size of the intercommunicating orifice, valves and plastic plugs with filters.
The above concepts are shown and described in U.S. Pat. Nos.: to Nichols 2,664,567; to Simpson 3,039,109; to Cade 3,600,714; to Morgan 3,609,764; to Dunning 3,761,959; to Larcer 3,787,893; to Rovani 4,023,213; to Gyory 4,038,700; to Schulz 3,287,613; and to Gooding 4,375,108.
The prior art types of shock-absorbing headgear inflatable liners with multiple compartments have been only partially effective. The types with layers of resilient foam plastic within the compartments do not distribute the force of an impact to the helmet over a very large area of the head of the wearer. The types with only air within the multiple compartments have of necessity been very thick compartments so as not to "bottom-out," i.e. instantaneously be completely compressed, to thereby transmit a large portion of the force of the impact to the head of the wearer. The types with valves or inserts with filters to control the flow of air through the intercommunicating air channels have been quite complicated for manufacturing.
The unique construction of this invention provides an inflatable liner with a thin profile to attenuate the force of an impact over as large an area as possible and the longest period of time with strength, durability and reliability to a high degree, together with inexpensiveness of construction.